purdy



NITED STATES PATENT OFFICE.

JAMES FENDER AND WVALTER O. PURDY, OF ST. JOHN, CANADA.

PROCESS OF PREPARING WIRE NAILS.

SPECIFICATION forming part of Letters Patent No.449,861, dated April 7, 1891.

, Application filed December 5, 1890. Serial No. 373,724. (No specimens.) Patented in Canada June 4, 1890, No. 34,477.

To all whom it may concern.-

Be it known that We, JAMES FENDER and WALTER O. PURDY, both subjects of the Queen of Great Britain, residing in the city of St. John, in the county of St. John, Province of New Brunswick, and Dominion 'of Canada, have invented a new and useful Improvement in the Process of Preparing ire Nails, (for which we have obtained Canadian Letters Patent, No. 34,477, dated June 4, 1890,) of which the following is a specification.

Heretofore nails have been treated mechanically in order to increase the frictional tendencies of their surfaces; but this method has several disadvantages incident thereto, such as expense, weakening the nail, making a ragged bore, &c.

The object of our invention is to roughen the surfaces of bright smooth wire nails by a chemical process, whereby the frictional tendencies or adhesion of saidsurfaces are appreciably increased at a very small cost without incurring the disadvantages incident to the mechanical methods.

WVith this object in view our invention consists in uniformly roughening the surface of wire nails either by oxidation or corrosion, or both, by the process and subprocesses here inafter fully described and claimed.

\Vire nails as they are delivered from the machine have a bri 'ht smooth surface, and in order to roughen their .surfaces according to our process they are first cleaned in the usual manner. The nails so cleaned are then placed in a bath of diluted sulphuric, muriatic, or other acid which by corrosion will roughen the surface of the nails. The nails after being sufficiently corroded are removed from the bath, washed with water, and then dipped into a bath containing a weak solution of lime-water or other alkaline solution, whereby any acid adhering to the nails will be neutralized and further chemical action checked. The nails are then dried by a hot blastorothersuitable means. The nails thus corroded and roughened have a dull dark appearance.

Oxidation and consequent roughening of the surface may also beaccomplished by placing the nails in a suitably-heated furnace, whereby the oxygen entering into combination with the iron will uniformly roughen the surface of the nails, thereby increasing its friction or adhesion. The nails thus oxidized will have a clouded bluish appearance.

Having thus described our invention, what we claim, and desire to secure by Letters Pat- JAMES PENDER. \VALTER O. PURDY.

Witnesses:

R. O. STOCKTON, A. A. STOCKTON. 

